2010 Camaro 3.6 L issues remain after PCM replacement

[Zimboy]

Hi All

It’s been a long road and still haven’t found the root of the issue.

2010 Camaro 3.6L V6 LLT
98 000KM
First codes that came up after scanning.
P0300
P0303
P1380
P0496
B2545 X2
B2699 X2
B3881 X2
B3882 X2
B3883 X2
B3950 X2
B3951 X2

C0750
C0755 X2
C0760

Changed the plugs and coils

P0300
P0302
P0304
P0306
P3145
B1637
P2179
Checked the VTT actuators with voltmeter on 2000 omms and both sides read 8.0. Swapped them side for side. No chance in codes.
Changed all four composition sensors and the crank position sensor.
Changed all fuel injectors
6 Nov
Codes
P0336
P0304
P0302
P0300
P0443
AC Delco plugs off Amazon had broken down and the electrodes were gone.
Replaced them with AC Delco from Lordco

To do
Clean valves run clean after
Try
“thinking fuel pressure regulator myself. symptoms seem to be about right. try moving the key to the 'run' position, and then removing it and repeating about 4 times before you start.” Tried this and it didn’t work.

26 Nov 2024
Current codes
P0300
P0301
P0302
P0304
P1380

Swap coils around

Engine flush and Changed oil

Cleaned intake valves. Quite a lot of buildup.

Compression test
#1 cylinder 165 PSI
#2 cylinder 170PSI
#3 cylinder 175 PSI
#4 cylinder 180 PSI
#5 cylinder 180 PSI
#6 cylinder 180 PSI

Fuel pressure 40-50PSI at intake manifold
No leaks found on Vacuum test


28 November
Removed downstream O2 sensors and cleaned them. No significant buildup.

Persistent issues with startups. Regardless if it’s hot or cold. Muffled backfiring heard in the intake.
Having the key on and pumping the accelerator before and while cranking will get the car started writhing 2 - 3 attempts.

GM dealership had it for over a week. Their only suggestion was the replace the PCM and they couldn’t get one.

Bought a Flagship One PCM. It would not rearm the key and was sent back TWICE. They cloned my PCM and the car will start but has the same issues as my original PCM.
Could it be the wiring harness?? I’m running out places to look lol.


Any help is appreciated.

[Zimboy]

Spoke to the dealership and they suggest changing the engine wiring harness. The issue is, they are discontinued and I am having a very hard time finding a second hand one that is in decent shape.
Does anyone have an ideas on what to do from here?

[Zimboy]

Thou no one has replied, thought I would update hoping someone can help.

After new cloned PCM from Flagship
B1621
P0404 Exhaust recirculation

P2179
P0404 Exhaust Gas Recirculation
C0303 vendor custom - NO INFO FOUND ON GOOGLE
P0504 break switch A/B correlation
B1621 vendor custom - NO INFO FOUND ON GOOGLE
P0101 MAP Range performance
P0104 MAP intermittent
P2179 System too lean off idle bank 2

P 0496 Evap emissions purge flow
P0443 Evap missions purge control valve

What I have done
I used some RTV sealant on the intake manifold gasket
Replaced a faulty Evap Canister purge valve (it was stuck open- drawing air when the power supply was disconnected)
Smoke tested both sides of the evap purge valve I replaced and hod no leaks.

Since I did the work and cleared the codes and did several trips, these codes didn't come back.
P 0496 Evap emissions purge flow
P0443 Evap missions purge control valve

But now have
P2179 bank 2
P2097 bank 1

The hard start is the only thing that has been constant

[KillboyPowerhead]

Sounds electrical-related. Lots of seemingly erratic and random codes. P0404 I believe refers to the EGR system which this engine doesn't even have (uses VVT to replicate the EGR function).

Google is telling me that B1621 for GM is something to do with the passenger side mirror; C0303 is rear propshaft (driveshaft) signal circuit high (there's a signal in the driveshaft?). http://westersgarage.eidnet.ca/obd2%...le%20codes.pdf